Short for "celebration" often used in the sports world after scoring a sick goal, having a filthydangle or in the normal world, after scoring with a hot babe. A celly is not a party; rather it is a brief expression of joy, such as a fist pump. Also used in general terms when the full word "celebration" is too lame and thus inappropriate for use.

"Dude did you see that sick celly by Gretzky after his game winner?"

"Hes havin' a fuckin giant celly right now... I bet he got some poontang earlier."

One of the greatest rewards when someone scores a goal in hockey. It can be a short celly, or a group celly in which the whole team joins in. In most bender leagues, a goal scored may not count unless you celly. Bigger games mean bigger cellys.

Coach just about shit his pants when Jimmy cellyed last night after he scored!